How Long Does it Take Wet Concrete To Fully Dry From The Time It Was Poured?

We’ve all come across a fresh patch of concrete at some point in our lives. Be it where new construction is taking place or a footpath being repaired. Concrete is literally everywhere around us, and thanks to its majestic nature, the modern cities that we know of would not exist without it. Apart from our cities infrastructure, concrete has been used for building cheap accommodations, however, the project wasn’t a big hit due to concrete being rather more suited for infrastructure than our homes.

Regardless, it is still a great question to ask how long it takes for concrete to dry once it's poured, and when it's feasible for you to walk over it?

Let’s find out:

How long does it take for concrete to dry?

Concrete is not as simple as it was a while back.

The buildings we live and reside in, the infrastructure that we use in our daily routine, all have a different kind of concrete used in it as the result needed to obtain from either of them is different.

Largely tho, concrete is made of an aggregate that is largely composed of sand and crushed stone. It may have some additional ingredients and then be mixed with cement and water. When water is mixed with the remaining ingredients, a chemical reaction takes place allowing concrete to take a hardened shape.

Oftentimes people confuse this reaction with being a physical one. However, this is purely a chemical reaction. In order to exactly know how long it will take for concrete to dry, the following things are to be kept in mind:

Factors that determine how long it will take:

To put it simply, there is way more to concrete what meets the eye.

Therefore, there is no definite answer to how long it will take concrete to dry since there are plenty of factors at play that defines and look into how and when concrete can reach its final destination.

These factors include:

1. Temperature & Humidity: the outdoor temperature of the concrete plays an important role in determining how long it will take for it to completely dry. In places where the sun shines brighter and longer, concrete will cure and dry much faster there. On the other hand, in places where temperatures stay low, concrete will cure much slower.
2. The moisture content of Concrete: another reason as to how long it will take concrete to dry is the water content of the concrete that is being poured. The higher the water content, the longer it is going to take for concrete to cure.
3. Types of concrete: there are plenty of types of concrete that are out there; from reinforced concrete to precast concrete to high-density concrete. Depending upon the reasoning given by the structure engineer, each type of concrete is going to take a different time to cure because of the ratio of water, cement, and sand/crush aggregate.

What is the curing and drying of concrete?

When we are talking about concrete, there are two very important processes that we need to take into account.

• Curing: once the concrete is poured, this is the first process that hardens concrete. Despite the batch of concrete being cured, some excess amount of water that is added to make concrete needs to evaporate. This evaporation of concrete that takes place is known as curing.
• Drying: on the other hand, drying is the process when after the concrete is cured, it starts to occur. This is usually when concrete starts to take its original state. This process can take months, and depending upon the conditions the concrete is exposed to, without conducting testing, one can never be too sure of if the concrete is dried or not.

What does curing do to concrete?

There are two main purposes of curing and these are:

• Curing allows moisture to retain itself within the slab. Therefore, this allows for the concrete to gain ample strength.
• With the help of properly curing concrete, it helps to improve strength, durability, water tightness, and resistance. Source

Therefore, in simple terms, curing is the most necessary part of concrete that helps it to gain strength properly. The strength of the concrete depends upon the “growth of crystals” that is present within the matrix of the concrete. These necessary crystals grow when the chemical reaction occurs when water is added to the cement, also known as hydration.

If there is not enough water then these crystals will not grow and as a result, the concrete will not cure properly and it will not be able to gain strength.

How long does it take for concrete to dry?

By considering all of the above factors, one thing is clear there is no defined answer to how long it will take for concrete to dry. However, with the set of site conditions, we can understand and estimate how long it will take.

One thing to note is that concrete never fully cures completely. It is always in its lifespan hardening bit by bit each day. Upon each passing day, cement is bonding with the water molecules, rendering the concrete harder.

However, the following is the time that will take for concrete to be “ready” for use:

If the conditions are right, the temperature is dry, concrete is able to handle foot traffic within the first 24 hours of its pour. If conditions are wet, this time frame can extend towards even 48 hours.

If again the conditions are right, and the temperature is dry, concrete can be labeled as fully hardened, it can take 24 days. However, if the conditions are not right, this can take up to 30 days.

Testing for ensuring that concrete is completely dry:

Now that there is a rough estimate of how concrete operates. There is a better picture that helps to understand how long it takes for concrete to dry. Although one thing is clear if you are still unsure, there are professional ways that you can use to fully satisfy yourself regarding if the concrete is dry or not.

Of course, no one can tell concrete is dry just by looking at it. Therefore, concrete moisture testing was introduced back in the 1960s, and the test has matured ever since giving a much more accurate result than before. The test is known as ASTM F2170 Standard. It's a good practice to put this test while doing a contract with your building contractor so that you are fully satisfied.

What makes this test so accurate is that it uses different sensors that are inserted within different depths of the concrete. By measuring the relative humidity that is trapped within the concrete, the sensors of the device can detect and can give you a closer estimate regarding if the concrete is dry or not.

Conclusion:

It is rather difficult to give an estimate regarding if the concrete is dry or not, or when will it dry. The answer is due to numerous factors that help to determine how fast a concrete can dry. Usually, if the temperature conditions are right and normal, you will be able to walk over the concrete path within the next 24 hours since it was poured.